As long as your devotion to blue is less than five, Thassa isn't a creature. (Each U in the mana costs of permanents you control counts toward your devotion to blue.)
At the beginning of your upkeep, scry 1.
1U: Target creature you control can't be blocked this turn.
Near Mint - $700
Lightly Played - $600
Moderately Played - $500
Heavily Played - $500
Damaged - $400
Near Mint Spanish - $700
Lightly Played Spanish - $600
Moderately Played Spanish - $500
Heavily Played Spanish - $500
Damaged Spanish - $400